WKWebview 获取网页加载内容的高度

> 方法一

- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation {

CGFloat height = 0.0;

    [webView sizeToFit];

    height = webView.scrollView.ContentSize.height;

    CGRect webFrame = webView.frame;

    webFrame.size.height = height;

    webView.frame = webFrame;

}

> 方法二

- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation {

[webView evaluateJavaScript:@"document.body.offsetHeight" completionHandler:^(id data, NSError * _Nullable error) {

  CGFloat height = [data floatValue];

    //ps:js可以是上面所写，也可以是document.body.scrollHeight;在WKWebView中前者offsetHeight获取自己加载的html片段，高度获取是相对准确的，但是若是加载的是原网站内容，用这个获取，会不准确，改用后者之后就可以正常显示，这个情况是我尝试了很多次方法才正常显示的

    CGRect webFrame = webView.frame;

    webFrame.size.height = height;

    webView.frame = webFrame;

}];

}

> 方法三:遍历WKWebView的所有子视图，找到中间的WKContentView,获取到它的frame设定给webView

- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{

    if(webView.subViews.count > 0) {

    for(UIView *view in webView.subViews) {

          if([view iskindOfClass:NSClassFromString:@"WKContentView"]){

          webView.frame = view.frame;

          }

  }